Ethylene Glycol → 2-Bromo-4-[1,3]dioxolan-2-yl-5-fluoro-pyridine

Reaction equation

[Br:1][C:2]1[CH:3]=[C:4]([C:7]([F:10])=[CH:8][N:9]=1)[CH:5]=[O:6].[CH2:11](O)[CH2:12][OH:13].O.C1(C)C=CC(S(O)(=O)=O)=CC=1>C1(C)C=CC=CC=1>[Br:1][C:2]1[CH:3]=[C:4]([CH:5]2[O:13][CH2:12][CH2:11][O:6]2)[C:7]([F:10])=[CH:8][N:9]=1

Participants

Procedure

A mixture of 2-bromo-5-fluoroisonicotinaldehyde (495 mg, 2.43 mmol), ethylene glycol (0.27 mL, 4.85 mmol) and p-toluenesulfonic acid monohydrate (508 mg, 2.67 mmol) in toluene (13.5 mL) was refluxed for 4 hours. The mixture was concentrated and taken up in CH2Cl2, washed with 1 M NaOH, dried over sodium sulfate, filtered and concentrated. The crude product was purified by flash chromatography on silica gel (cyclohexane/EtOAc) to give INT 44.